Evaluation of Ultrasound and PET/CT in the Diagnosis and Monitoring of Giant Cell Arteritis

The aim of this project is to prospectively evaluate the diagnostic accuracy of different imaging tools in specific giant cell arteritis disease subsets before and after treatment initiation. Diagnostic tools with high sensitivity and specificity are a prerequisite for optimal treatment of GCA patients. Specifically, the diagnostic accuracy of ultrasound (US) as compared to 18F-FDG PET/CT in new-onset, treatment naïve large vessel(LV)-GCA patients is investigated. Furthermore, long-term follow up including US, 18F-FDG PET/CT and cross sectional imaging is performed to explore the potential of imaging as monitoring and prognostic tools. In this observational cohort, the diagnostic accuracy of 18F-FDG PET/CT after three and ten days of glucocorticoid treatment in the subset of LV-GCA patients and the diagnostic accuracy of 18F-FDG PET/CT in cranial artery inflammation in new-onset, treatment naïve c-GCA patients as compared to a control group of patients with a previous diagnosis of malignant melanoma was also evaluated and is registered elsewhere (ClinicalTrials.gov Identifier: NCT03285945 and NCT03409913, respectively)